In our times, when an average email account is flooded with tens of spam emails each day, and people are afraid to post their email addresses on internet, Skype offers to potential spammers tons of valid details about Skype accounts.
Just try to do a simple search in Skype and in an instance it will be displayed to you entire lists of people that match your search. Using all the parameters available in the search tools, such as language, age, country a potential spammer may find targets in an easy way.
Of course, Skype offers you in Settings -> Privacy options section the ability to specify that you want to accept chats or phone calls only from people on your list but I couldn’t find any option to make my entire profile private. Skype states that the fields from your profile are optional but the fact is that a lot of persons fill up those fields to show more information to their friends.
In a recent post in Skype journal, somebody discovered a way to find out if a person is online or not, even if the status is set to Invisible. He used the information provided by the webcam symbol which apparently due to a bug in Skype stays visible even if the person turned invisible.